Maximal oxygen uptake: New and more accurate predictive equation

The Effects of Exercise Training on Functional Capacity and Quality of Life in Patients with Rheumatoid Arthritis: A Systematic Review

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation. The purpose of this systematic review is to evaluate the effectiveness of exercise training on functional capacity and quality of life (QoL) in patients with RA. We performed a search in four databases, selecting clinical trials that included community or outpatient exercise training programs in patients with RA. The primary outcome was functional capacity assessed by peak VO2 or the 6 min walking test, and the secondary outcome was QoL assessed by questionnaires. Seven studies were finally included, identifying a total number of 448 patients. The results of the present systematic review show a statistically significant increase in peak VO2 after exercise training in four out of seven studies. In fact, the improvement was significantly higher in two out of these four studies compared to the controls. Six out of seven studies provided data on the patients' QoL, with five of them managing to show statistically significant improvement after exercise training, especially in pain, fatigue, vitality, and symptoms of anxiety and depression. This systematic review demonstrates the beneficial effects of exercise training on functional capacity and QoL in patients with RA.

Does Hyperbaric Oxygenation Improve Athletic Performance?

ABSTRACT

Šet, V, and Lenasi, H. Does hyperbaric oxygenation improve athletic performance? J Strength Cond Res 37(2): 482-493, 2023-Hyperbaric oxygen (HBO) has been suggested to affect oxygen availability and performance, and delay the onset of fatigue. Many mechanisms of HBO-induced alterations have been proposed, including modulation of various metabolic pathways, and the antioxidant defense mechanisms. As exercise per se affects similar aspects, it is tempting to speculate that simultaneous application of both, exercise and HBO might have synergistic effects. The aim of this review was to search through the currently available literature and evaluate the effect of acute exposure to HBO on exercise performance, potential effects of a combination of HBO and physical training, and to elucidate some possible mechanisms behind. We conducted searches in the PubMed and Scopus databases (search term: "hyperbaric" AND "oxygen" AND "exercise") and in relevant hyperbaric textbook and assessed potentially eligible full texts for details. Meta-analysis could not be performed because of a few available and rather heterogeneous studies. Twenty-seven studies were included in the final assessment (14 on exercise during HBO, 9 on exercise following HBO, 4 on applying HBO during recovery and rest between exercise bouts, and 3 on a combination of HBO and training). The results are contradictory, showing either positive or none ergogenic effects. There is some risk of bias and placebo effect. Discrepant findings of the available studies might partly be explained by different protocols applied, both regarding HBO and exercise intensity and regimen. There is a need for further research with well-designed trials to evaluate the effect of HBO on performance before recommending it to routine use in athletes.

Is there an association between total physical activity level and VO2max among fitness club members? A cross-sectional study

Background

Since cardiorespiratory fitness is an important predictor for all-cause mortality, it is of interest to know if meeting the physical activity (PA) recommendations is associated with higher levels of maximal oxygen uptake (VO_2max). We aimed to investigate the association between total PA level given as counts per minute (cpm) and minutes in moderate-to-vigorous PA (MVPA), and VO_2max in new fitness club members.

Methods

A total of 62 men and 63 women (≥ 18 years), defined as healthy (no disease considered to hinder PA) participated in this study. VO_2max (mL kg⁻¹ min⁻¹) was measured with a cardiopulmonary exercise (modified Balke protocol), and total PA level was measured with ActiGraph GT1M for seven consecutive days. All participants accumulating ≥ 10 h of activity recordings ≥ 4 days were included in the data analysis. To examine associations between PA level and VO_2max, a Pearson correlation and a multiple linear regression analysis adjusted for covariates were used.

Results

VO_2max (mL kg⁻¹ min⁻¹) was 40.5 ± 7.2 in men and 35.1 ± 6.0 in women. Total PA level (cpm) and MVPA (min) were 352.4 ± 123.4 and 260.0 ± 132.6 in men and 361.4 ± 103.8 and 273.2 ± 137.0 in women. Total PA level (men: r = 0.346, p < 0.01, women: r = 0.267 p < 0.01) and MVPA (men: r = 0.359, p =  < 0.01, women: r = 0.236, p = 0.03) was associated with VO_2max. When adjusting for age and body fat percentage, total PA level and MVPA were no longer associated with VO_2max (men: p = 0.11 and p = 0.79, women: p = 0.40 and p = 0.61). In men, age (β = − 0.469 p < 0.01) and body fat percentage (β = − 0.483, p < 0.01) were the strongest predictor for VO_2max. For women, body fat percentage was the strongest predictor for VO_2max (β = − 0.483, p < 0.01).

Conclusions

Total PA level and MVPA were associated with VO_2max, but the association was low and diminished when adjusted for age and body fat percentage. Body fat percentage (men and women) and age (men) were more strongly associated with VO_2max than total PA level and MVPA.

Differential Expression of Genes Associated with Chromatin Modifications in Skeletal Muscle during Aerobic Training Program

Introduction: Skeletal muscle plasticity in exercise can be modulated by epigenomic events such as gene silencing, histone modifications and DNA methylation. In this context, our objective was to analyze the expression of genes associated with chromatin modifications in human muscle biopsies of vastus lateralis after a 20 week training program. Methods: Using data from DNA microarray experiments registered in the NCBI GEO DataSet database GSE117070, we calculated the Z ratio values as the criterion to evaluate the differential expression of genes associated with chromatin modification during aerobic training in skeletal muscle. Using the web interface GENEMANIA, we built a co-expression interaction network with the overexpressed genes. We compared Z-score values obtained from pre-trained and post-trained samples through nonparametric tests. Results: We found 10 overexpressed genes after the 20 week training program, namely, EZH1, KMT2A, KMT2D, KDM4C, KDM6A, CREBBP, HDAC10, HDAC4, DNMT3L, and H2AX. The most relevant biological processes obtained from the network included chromatin organization (FDR 9.04×10-9) and histone modification (FDR 9.04×10-9). Conclusions: In skeletal muscle, after aerobic training, there is overexpression of genes associated with the modification of the chromatin through alterations in histones and DNA, resulting in epigenetic transcriptional changes.

Monitoring functional capacity in heart failure

This document reflects the key points of a consensus meeting of the Heart Failure Association of European Society of Cardiology (ESC) held to provide an overview the role of physiological monitoring in the complex multimorbid heart failure (HF) patient. This article reviews assessments of the functional ability of patients with HF. The gold standard measurement of cardiovascular functional capacity is peak oxygen consumption obtained from a cardiopulmonary exercise test. The 6-min walk test provides an indirect measure of cardiovascular functional capacity. Muscular functional capacity is assessed using either a 1−repetition maximum test of the upper and lower body or other methods, such as handgrip measurement. The short physical performance battery may provide a helpful, indirect indication of muscular functional capacity.